[PATCH v3 6/9] net/gve: free ctx mbuf if packet dropped after first segment

[Joshua Washington <joshwash@google.com>]

GVE GQ has support for multi-descriptor RX. It is possible for a packet
to be dropped after the first descriptor has been processed an mbuf has
been added to the context. In such a case, the mbuf head should be freed
before clearing the context so that mbufs aren't leaked.

In addition, clear mbuf from sw_ring after adding the packet to the
context to avoid double-freeing buffers that have not been reposted, but
have been reported to the application.

Fixes: 496d4d2c8b54 ("net/gve: support jumbo frame for GQI")
Cc: stable@dpdk.org
Signed-off-by: Joshua Washington <joshwash@google.com>
Reviewed-by: Jasper Tran O'Leary <jtranoleary@google.com>
---
 drivers/net/gve/gve_rx.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/gve/gve_rx.c b/drivers/net/gve/gve_rx.c
index cda87af294..567b82d020 100644
--- a/drivers/net/gve/gve_rx.c
+++ b/drivers/net/gve/gve_rx.c
@@ -205,6 +205,8 @@ gve_rx_burst(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 		if (gve_rx(rxq, rxd, rx_id)) {
 			if (!ctx->drop_pkt)
 				rx_pkts[nb_rx++] = ctx->mbuf_head;
+			else if (ctx->mbuf_head != NULL)
+				rte_pktmbuf_free(ctx->mbuf_head);
 			rxq->nb_avail += ctx->total_frags;
 			gve_rx_ctx_clear(ctx);
 		}
-- 
2.55.0.rc2.803.g1fd1e6609c-goog